Former Iranian president Mohammad Khatami has called for a national referendum on the legitimacy of the ruling government, according to Monday postings on several pro-reform websites.
Khatami was quoted on the websites as saying millions of Iranians have lost their faith in government in the wake of the contentious June 12 presidential election.
Official results indicate incumbent President Mahmoud Ahmadinejad prevailed by a comfortable margin, but leading opposition candidate Mir Hossein Mousavi has disputed that count and called the vote rigged.
"Durability of order and continuation of the country's progress hinge on restoring public trust," said Khatami, according to the sites.
"From the start, we said there is a legal way to regain that trust. I openly say now that the solution to get out of the current crisis is holding a referendum."
Ever since the election, Iran has been plunged into political uncertainty, as hundreds of thousands of opposition supporters have taken to the streets to protest the results of what they believe is a fraudulent election.
The Iranian regime, headed by Ahmadinejad and Supreme Leader Ayatollah Ali Khamenei, has cracked down on dissent, restricting large public gatherings and silencing both local and foreign media.
Referendums can proceed only with the permission of Khamenei, who has declared the results of the elections valid.
Shortly after news of Khatami's referendum call broke, Khamenei sounded a warning call to dissenting politicians.
Hurting Iran's security was "the biggest vice," he said, adding that "anybody who drives the society toward insecurity and disorder is a hated person in the view of the Iranian nation, whoever he is."
All popular votes in Iran are monitored by an oversight body, the 16-member Guardian Council headed by Khamenei. Khatami, however, proposed that a neutral body, such as the Expediency Council, should monitor the proposed referendum instead.
Reformists have accused the Guardian Council of openly supporting Ahmadinejad in the election dispute.
The Expediency Council is a powerful clerical body that arbitrates disputes between the legislature and the government. It also advises Khamenei.
Khatami, a staunch Mousavi supporter, was elected president in 1997 and 2001, and has been vocal in his criticism of the ruling regime.
Earlier this month, he released a statement accusing Iran's leadership of a "velvet coup against the people and democracy." He lashed out at what he termed "a poisonous security situation" in the wake of violent street protests.